A driving method and apparatus for a light source element of an optical pickup for reading and writing data from and to an optical data includes generating an error signal when a tracking error signal is higher than a first level or is lower than a second level and, if the error signal is active, supplying the light source element with a driving signal suitable for data read operations independent of whether the user selects read mode or write mode. As a result, when there is a tracking error the power of the device signal corresponds to that normally presented during a read mode, and this power is insufficient to write data onto the disc. Thus, data is not written over other desired data when an abnormal tracking error occurs.
Legal claims defining the scope of protection, as filed with the USPTO.
1. A driving apparatus for a light source element included in an optical pickup for reading and writing data from and to an optical disc, comprising: a mode selector for generating a mode signal corresponding to a user-selected read/write mode; a reference power data generator for detecting write reference power data and read reference power data from data read from said optical disc and for outputting the detected data; a first drive signal generator for generating a reading drive signal based on said read reference power data; a second drive signal generator for generating a writing drive signal based on said write reference power data; an error discriminator for receiving a tracking error signal generated in accordance with the movement of the optical pickup, and for generating an error signal which is active when an abnormal tracking error occurs; and a selector for selecting the reading drive signal if the error signal is active and otherwise selecting between the reading drive signal and the writing drive signal based on the mode signal, and supplying the light source element with the selected drive signal, wherein the reading drive signal causes the optical pickup to be operated at a power level suitable for reading data, and the writing drive signal causes the optical pickup to be operated at a power level suitable for writing data; wherein said selector comprises: a logic operator for receiving the error signal and the mode signal to produce a selecting signal; and a multiplexer for selecting one between the outputs of said first and second drive signal generators in accordance with the output of said logic operator.
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April 8, 1994
May 8, 2001
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